No other devices are allowed to hold a copy Error

[dhanad]

I have 2xTitan RTX Nvlinked. Been working on a scene so far without any issues. Until recently, I began to get this error. Only way to get rid of the error is if I hide some geometry, or textures that are being loaded for geometry. I am on Maya 2020.2 with the latest Arnold.

My question is, shouldn't 48GB of VRAM be enough, it seems like the scene is taking up 19GB. What does this mean "no other decices are allowed to hold a copy" ? Is it throwing this error when going out of core or something?

00:04:02 19425MB ERROR | [gpu] an error happened during rendering : Unknown error (Details: Function "_rtCommandListExecute" caught exception: Assertion failed: "!targets.empty() : Buffer abandoned but no other devices are allowed to hold a copy", file: <internal>, line: 683)

[dhanad]

I have tried to follow this thread: https://answers.arnoldrenderer.com/questions/24902/arnold-gpu-for-maya-error.html

And seems like lowering the subd does help. That is a bummer, so NVlink does not help in terms of combining memory from NVlinked cards in case of Arnold GPU? So essentially Arnold GPU is working with max limit of 24GB only since the Titan RTX is only 24GB on each card.

My understanding was wrong in this case, I thought it loads same copy in both cards and as soon as more memory is needed it would use the second card's memory for working with the data.

[thiago.ize · Accepted solution]

Hi, this might be a bug inside of NVIDIA's Optix 6, which comes with the gpu driver and I believe is being investigated by NVIDIA. When this is fixed, you should be able to have scenes that use more than 24GB.

[dhanad]

Thanks Thiago. Good to know I am not limited to 24GB, was freaking out because of the investment I made in the pair of Titans. Fingers crossed for a fix soon.